Electric-arc lamp



(No Model.)

B. A. EDWARDS.

ELECTRIC ARC LAMP.

N0. 275,168. Patented Apr.3, 1883.

UNITED STATES PATENT OFFICE.

EDGAR A. EDWARDS, OF CINCINNATI, ASSIGNOR TO 0. M. GOTTSOHALL, TRUSTEE, OF DAYTON, OHIO.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 275,168, dated April 3, 1883.

' Application filed October 17, 1882. (N0 model.) i

To all whom it may concern:

Be it known that I, EDGAR A. EDWARDS, a citizen of the United States, and a resident of Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Electric Lamps, of which the following is a specification.

My invention relates to an improvement in electric lamps, and it relates particularly to that class shown in Letters Patent No. 257,678, granted me May 9,1882; and it consists in improvements thereon, as will be hereinafter fully explained,

Figure l is a perspective View of my improved electro-magnets with the mechanism for regulating one of the carbons of the lamp attached thereto. Fig. 2 is a view partly in section on line a: m, Fig. 1.

A represents a sectional part of the magnetcase, which is preferably constructed as shown in my former patent.

B B represent a U-shaped magnet; O 0, another U-shaped magnet. These magnets are constructed and wound as shown in my said former patent, B B being the principal or coarse-wire magnet, and O C the differential magnet wound with line wire.

D represents the carbon-holder, and a b c the leverand clutch mechanism connecting the carbon-holder to the magnets for adjusting it by means ofthe differential magnetic intensity induced by the magnets.

E E represent the axial cores of the magnets, each of which is made of a single piece of metal, instead of being made of two pieces of metal, as shown in my former patent, and these cores are connected by a diamagnetic yoke, which is attached to the solid core in any desired manner. Thus I magnetically separate the two sets of magnet-cores, and yet unite them by a diamagnetic yoke or crosshead, so that both must move simultaneously as actuated by varying magnetic currents.

The magnets must be wound so that the polarity of the limbs B and G are of the same sign or kind, while the limbs B and 0 must be of the opposite sign. The upper and lower ends of the spools or magneto-oils are attached directly to the soft-iron case, so as to form a continuous magnetic circuit; but the cores being united by a diamagnetic yoke, there is no tendency of neutralization of the varying magnetic intensities exerted upon the yoke, as is the case when made of soft iron, as in my former patent granted May 9, 1882.

I have found by repeated experiments that a more sensitive movement and accurate adjustment of the carbon can be obtained by making the cores of the magnets solid and uniting them by a diamagnetic yoke than could be obtained by the divided cores and soft-iron yoke shown and described in my former patent.

G represents a common dash-pot; H, the piston or plunger rod, the upper end of which is bent so as to be connected to the yoke F to regulate the movement of the cores of the magnet. I have found by experiment that the dash-pot is more effective and the lamp more easily kept in order by using an outside dashpot instead of making the (lash-pot inside of the magnet, as in my former patent.

I claim- 1. The combination, in an electric lamp, of two sets of magnets, having the solid cores E E connected together by a diamagnetic yoke, substantially as herein set forth.

2. The combination, in an electric lamp, of two sets of magnets, having the solid cores E E connected together by a diamagnetio yoke, and clutch mechanism for regulating the carbon-holder connected thereto, substantially as herein set forth.

3. The combination, in an electric lamp, of two sets of magnets, having the solid cores E E, the diamagnetic yoke, the clutch mechanism for regulating the carbon-holder, and the dash-pot G, and plunger-rod H, which, together with the clutch mechanism, is centrally connected to the yoke, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

EDGAR A. EDWARDS. Witnesses:

Jno. E. JoNEs,

J. H. CHAS. SMITH. 

